A concentrated solar energy system includes a photovoltaic cell, an optical concentrator, a heat removal system, and means for providing thermal contact between the photovoltaic cell and the heat removal system. The optical concentrator is configured to direct concentrated solar energy to the photovoltaic cell such that the photovoltaic cell generates electricity and heat. The heat removal system removes heat from the photovoltaic cell. The means for providing thermal contact provides an effective thermal conductivity per unit length between the photovoltaic cell and the heat removal system of greater than about 50 kilowatts per square meter per degree Celsius.